Study On Extraction And Activity Of Enzymatic Polypeptides From Peony(Fengdan)Seed Meal For Oil

Peony seed meal is a by-product in the production of peony seed oil.With the mass production of peony seed oil,a large amount of peony seed meal will be produced every year,and peony seed meal is rich in protein.If not used,it will cause serious waste.This study takes Peony(Paeonia ostii T.Hong et J.X.Zhang)as the research object.Six kinds of protease(papain,trypsase,pepsin,protemax,neutral protease and alkaline protease)were used to hydrolyze peony seed meal and six kinds of enzymatic polypeptides were obtained.The activity of the enzymatic polypeptides was studied by antioxidant experiment and in vivo experiment in mice.The enzymatic polypeptides is prepared by extracting from peony seed meal.First,peony seed meal after oil extraction is subjected to de-oiling and de-sugar treatment.Then the peony seed meal is hydrolyzed by 6 kinds of proteases.According to the yield,two kinds of enzymes are selected:compound protease and alkaline protease.Determine the best enzymolysis conditions,through single factor and orthogonal experiments.The optimal enzymolysis conditions for the protemax are as follows:the amount of enzyme added is 24000 U·g-1,the extraction temperature is 55?,the extraction time is 2 h,the material-liquid ratio is 1:40 g·mL-1,and the pH is 5.The optimal enzymolysis conditions for alkaline protease are as follows:the amount of enzyme added is 36000 U·g-1,the extraction temperature is 55?,the extraction time is 2 h,the ratio of material to liquid is 1:40 g·mL-1,and the pH is 11.The composition and amino acid composition of enzymatic polypeptides were studied.Studies have shown that enzymatic polypeptides mainly contain protein and a small amount of carbohydrates.The protein contains 8 kinds of essential amino acids,and the content of essential amino acids is very rich.It can meet the protein nutritional needs of children in international standards and has good nutritional value.The surface activity and emulsification stability of the enzymatic polypeptides were studied.Studies have shown that the oil absorption and emulsification properties of the alkaline protein method of enzymatic polypeptides are better than those of the protemax enzymatic method.The enzymatic polypeptides prepared by the alkaline protease method and the peony seed oil are mixed and emulsified.Accelerated oxidation method is used to determine the oxidation stability of emulsionThe results showed that enzymatic hydrolysis of peptides can prevent peony seed oil from being oxidized and decomposed.The activity of the enzymatic polypeptides was studied by antioxidant experiment and in vivo experiment in mice.In the 5 kinds of antioxidant experiments,the enzymatic polypeptides all have good antioxidant activity,and the comprehensive antioxidant capacity of the alkaline protease method is stronger.Enzymatic polypeptides were fed to mice to supplement protein-nutrition mice.In the high-dose group,enzymatic polypeptides can increase the protein content in mice.At the same time,it can effectively promote the increase of CAT and SOD,and inhibit the production of MDA.Therefore,the peony seed meal enzymatic polypeptides has important nutritional value and development potential.